Corrosion coupons machined from stainless steel and nickel alloy tubulars were exposed to NACE Solution in both the uncoated and coated condition. These samples were evaluated following exposure on the basis of (1) nature of corrosion, (2) extest of general and localized (pitting and crevice) corrosion, and (3) condition of coating.

Corrosion rates and observed corrosion type are conducted. The tests indicate that caustic additions that provide a pH around 12 area beneficial and that the arsenite inhibitor is, in general, more effective than the chromate inhibitor for titanium alloys and the cupro-nickel alloy. Chromate is slightly more effective for carbon steel.

The present study involved the evaluation of selected stainless and nickel base alloys in the following acidizing media: (1) 15 percent HCl, (2) 28 percent HCl, (3) 12 percent formic acid and (4) 13 percent HCl/2 percent HF. Tests were conducted both with H2S and with CO2 at 200 F and 400 F. Two different inhibitors were used in each acidizing media. Acidizing media were generally found to be very aggressive to stainless and nickel base alloys. In most cases, the 22 Cr and 25 Cr duplex stainless...

A series of autoclave corrosion tests were conducted to simulate conditions in the steam generator. Nal-Prep III, a commercial passivating treatment, produced only slight reduction in the pitting rate on carbon steel. Type 316 stainless steel and more highly alloyed stainless steels showed no or low pitting and no stress corrosion cracking in the steam generator conditions. Alloys with low or no molybdenum such as Type 304 showed some pitting at the liquid-vapor interface. Electrochemical tests ...

The results of this investigation indicate that the two materials evaluated (AISI 4140 steel and 2-1/4 Cr-l Mo steel) have comparable resistance to SSC in the high pressure, sour environment. In addition, at 75 F the SSC behavior of both materials is comparable to that observed in NACE solution exposure tests previously conducted. It was also observed that samples exposed to the H2S/CO2/brine environment at 300 F in the stressed condition before testing at 75 F, showed a substantial reduction in...